[This is part 1 in a series of excerpts of the book The Moral Case for Fossil Fuels by Alex Epstein]
Humanity needs as much energy as it can get.
First: What exactly is energy? The technical definition is “the capacity to do work” but my favorite way to sum it up is with two words: “machine calories.”
Every human being runs off the calories he or she consumes; those calories are our energy, our ability to act. If we run out of calories, we can’t act—we die.
The same is true of the machines we use to improve our lives. Whether we’re talking about the ultrasound and incubation machines that enable us to save babies, the computers that enable us to gain or discover knowledge, the planes that enable us to visit family members across the globe, or the factories that make it possible for all of those things to be affordable, every aspect of our lives is improved dramatically by machines. Those machines live on energy—their ability to act—and without energy, they are the same as the energy-starved machines that can’t save the Gambian babies: useless.
And we desperately need machines to do work for us because we are naturally very weak. Without machines to help us, we don’t have anywhere near all the energy that we need to survive and flourish.
The average human being needs about 2,000 calories a day to give him enough energy to do everything he needs to do—from going to the office to taking a walk to manual labor to sleeping. That’s equal to 2,326 watt-hours, which is the amount of energy it takes to power a 100-watt lightbulb for 23.26 hours. Essentially, your body uses the same amount of energy as a 100-watt lightbulb. Pretty interesting, right?
The more energy you are using at any time, the more power you are exerting. Power is defined as the rate of energy use. Power is energy in action; the gasoline is the energy, the engine turns it into power.
And here’s where the problem of human weakness comes in. We are not very powerful—about one tenth as powerful as a horse that’s one two-hundredth the power of the average car—and thus we can use only so much energy and do only so much work, not nearly enough for a good standard of living.
The story of energy for over 99 percent of history is that human beings couldn’t get enough of it to live, and if they could, they could make very limited use of it, because they lacked power. Thus they spent their lives engaging in grueling physical labor just to keep their bodies going long enough to engage in the next day of grueling physical labor.
Consider the amount of energy at the average American’s disposal. The average American’s total machine energy use is 186,000 calories a day—ninety-three humans (or twenty-three Michael Phelpses)!5 This is one of the greatest achievements in human history. In the past, before modern energy technology, the main way to overcome the problem of human weakness was putting others into a state of servitude or slavery—which meant that only some could prosper, and at the great expense of others. But with machine energy and machine servants, no one has to suffer; in fact, the more people, the merrier.